A method for making a fibrous layer for fuel cell applications includes a step of combining a perfluorocyclobutyl-containing resin with a water soluble carrier resin to form a resinous mixture. The resinous mixture is then shaped to form a shaped resinous mixture. The shaped resinous mixture includes perfluorocyclobutyl-containing structures within the carrier resin. The shaped resinous mixture is contacted (i.e., washed) with water to separate the perfluorocyclobutyl-containing structures from the carrier resin. Optional protogenic groups and then a catalyst are added to the perfluorocyclobutyl-containing structures.